Another possible explanation is that ethnical cleansing works and the different groups don't meet each other that often anymore.
Like when they run out of villages to burn in the Sudan, we do not blame the United Nations (of tyrants too) for the lack of troops, it must be our leaders and not their leader’s attitude and analysis that is responsible for the mess.
“On the basis of what we said about Iraq while confronting aggressions, the world now needs to abort the US aggressive schemes, including its aggression on the Afghan people, which must stop.
Again we say that when someone feels that he is unjustly treated, and no one is repulsing or stopping the injustice inflicted on him, he personally seeks ways and means for lifting that justice. Of course, not everyone is capable of finding the best way for lifting the injustice inflicted on him. People resort to what they think is the best way according to their own ideas, and they are not all capable of reaching out for what is beyond what is available to arrive to the best idea or means.
To find the best way, after having found their way to God and His rights, those who are inflicted by injustice need not to be isolated from their natural milieu, or be ignored deliberately, or as a result of mis-appreciation, by the officials in this milieu. They should, rather, be reassured and helped to save themselves, and their surroundings.” (Saddam Hussein Shabban 13, 1422 H. October 29, 2001.)
“The Arab League has rejected any sanctions or international military intervention as a response to the crisis in Sudan's Darfur region…On 30 July, a UN resolution gave Sudan 30 days to bring Arab militia under control or face international action.” (Monday, 9 August, 2004, 03:23 GMT 04:23 UK)
BBC NEWS | World | Africa | Arab League backs Sudan on Darfur
“Some voices have risen on the part of some peoples, journalists, writers, and, in a very restricted way, the voices of those who are preparing themselves, in the shadow, to replace the rulers there. Nevertheless, the latter are still hesitant voices that deal with the situation in the light of the balance of interests of the posts they expect to occupy, and of the influence of the centers of power.” (Saddam Hussein Shabban 13, 1422 H. October 29, 2001.)